Inertia operated control device



Nov. 28, 19444. G. K. NEWELL INERTIA OPERATED'CQNTROL DEVICE lNVENTbR IGEORGE KNEWELL' Original Filed April 20, 1940 Patented Nov. 28, 1944UNITED- STATES PATENT orrice v INERTIA OPERATED CONTROL DEVICE JreorgeK. Newell, near Pitcairn, Pa., assignor to The Westinghouse Air Brake.Company, Wilmerding, Pa., a corporation of Pennsylvania Originalapplication April 20, 1940, Serial No. 330,805. Divided and thisapplication February 3, 1942, Serial No. 429,384

Claims.

' sive to the rotative deceleration of a vehicle wheel have beenemployed previously for the purpose of detecting a slipping condition ofthe wheel and arranged to cause a rapid release of the brakes associatedwith the wheel so as to cause restoration thereof to a speedcorresponding to vehicle speed before it can decelerate to a lockedcondition and slide.

The term slipping condition as applied herein to a vehicle wheel refersto the rotation of the wheel at a' speed greater or less than a speedcorresponding. to vehicle speed occurring respectively in response tothe application of propulsion torque or braking force on the wheelsufficient to exceed the limit of adhesion between wheel and roadsurface and rail. Theterm sliding condition or fsliding refers solely tothe dragging of a vehicle wheel along the road surface or rail in alocked or non-rotative condition. The two terms are thus distinct inmeaning and the difference in their meanings should be borne in mind.

Heretofore known rotary inertia devices employed in brake controlequipment comprise essentially a fiy-wheel rotatively mounted onbearings and driven through a resilient connection, usually a spring,according to the rotational speed of a shaft on which the fly-wheel isjournaled. It has been found that when a rotary More particularly, tionto providea rotary inertia operated control device, of the characterindicated in the foregoing object, in which the fly-wheel is mounted forrotation with a driving shaft independently of any bearings by means ofannular web portion of rubber or other similar material.

It is another object of my invention to provide a rotary inertiaoperated control device, of the character indicated in the foregoingobjects, in which the resilient web supporting the fly-wheel on thedriving shaft or spindle isprelnforced in a manner to resist undesireddistortion thereof and to limit the degree of rotative movement of thefiy-wheel'relative to its driving shaft.

Other objects and advantages of the invention will appear in thefollowing more detailed description thereof, taken in conjunction withthe accompanying drawing, in which Fig. 1 is a plan view of one form ofinertia responsive device constructed in accordance with the invention;

inertia device of this type is mounted in direct association with theaxle of a wheel truck of a railway car, the constant shock and vibrationincident to travel of the car along the rails produces a frettingcorrosion of thebearings supporting the fly-wheel. This corrosion, intime, increases the bearing friction and consequently interferes withthe uniformity of response of the fly-wheel to a given rate ofdeceleration of acceleration of the vehicle wheel.

It is an object of my present invention to provide a rotary inertiaoperated control device of novel construction adapted to be employedparticularly in railway service for brake control or other purposeswhich obviates the problem of fretting corrosion of bearings supportingthe flywheel.

Fig. 2 is a diagrammatic view of an anti-wheelslider apparatus embodyingmy improved flywheel device, the latter being shown as sectionedsubstantially along the line 2-2 of Fig. 1; and

Fig. 3 is a fragmentary view illustrating another form of fly-wheeldevice which may be substituted for that shown in Fig. 1.

Referring to Figs. 1 and 2 of the drawing, the

anti-wheel-slider mechanism embodying my improved fly-wheel device maycomprise a rotary shaft 5, which is operatively connected to a wheel ofthe vehicle, not shown, and the fly-wheel device 6, which includes a.central hub member I that is keyed or otherwise secured to the shaft. Inaddition to the hub member I the fly-wheel device 6 includes a flexibleweb portion 9, which is formed of rubber composition or the like, and istapered in cross section, as may be seen in .Fig. 2, the innermostradial portion of the web member being of greater thickness than theouter radial portion thereof. Supported by the web member 9 incoaxiabalignment with the hub member I is an annular inertia member l0,the

inner surface of which has formed thereon a pair" of annular shoulders Hadapted to grip the outer portion of the web member. It will beunderstood that the flexible web member 9 is adapted to be firmlysecured to the hub member I and to the annular inertia member Ill by asuitable bonding means.

Formedin the web member 9' are a plurality of circumferentially spacedapertures I5, which it is an object of my inven a flexible resilient areseparated by relatively narrow rib portions II and are adapted toreceive reenio'rcing tubular elements I]. By reason of thisconstruction, the fly-wheel member 6 is adapted to permit a relativelylarge rotary deflection of the inertia member It with respect to the hubmember I, the relatively narrow rib portions ltoiithe flexible webmember being designed to yield readily. On the other hand, the rigidtubular elements II are adapted to receive compressive stresses on therelatively broad surfaces thereof for preventing collapse ofthe ribportions 16 or undue deflection of the-inertia member Ill in'an axialdirection and out of concentric alignment with the hub member I. It willthus be apparent'that the flexible web member 9 is arranged to act as acushion for the relatively heavy inertia. member Ill and to resistdisplacement of that member with respect to the hub. member I duringrotation of the shaft 5, while therigid tubular elements I! in effectconstitute bearing rollers imbedded in a viscous bearing race forfacilitating rotary displacement of the annular member in response to anangular deflecting force.

Although my improved fly-wheel device may be employed for actuatingvarious types of brake controlling mechanism and the like, it is in thepresent embodiment arranged to control a switch mechanism comprising apair of flexible contact elements 20, which are connected together andare mounted on the hub member I, and an intermediate contact element 2|secured to the annular inertia member ill and extending into operativealignment with the contact elements 20. As is shown in Fig. 2, thecontact element 2| is connected by a conductor 22 to 'a slip ring 24that is secured to an insulating member 25 carried by the shaft 5, andthe two contact elements are similarly connected by means of a conductor21 to a sli ring 28, also mounted on the mem er.

Any desired type of fluid pressure brake apparatus may be arranged forcontrol by the inertia responsive device already described, but forillustrative purposes I haveshown only certain insulating brakecontrolling valve 'initiate supply of fluid under pressureto the supplypipe 33, irom aseaen 'wheel device I are rotated at a speedcorresponding to the rotative speed of the associated wheel ofthevehicle. To eflect an application of the brakes, the operator causesoperation of the usual equipment, notshown, to

which fluid flows past the open valve and through pipe 39 to the brakecylinder device 33, which responds to theincrease of fluid pressure toapply braking force to the wheel. If the wheel is braked too heavily,and is thereby caused to decelerate at an excessive rate essentialelements of a brake apparatus, includ-" ing a brake cylinder device 30which is operative when supplied with fluid under pressure to exertbraking force on the wheel associated with the fly-wheel'device 6, arelease magnet valve device 3|, a cut-01f magnet valve device 32, and afluid pressure supply pipe 33, which is adapted to be supplied withfluid under pressure by operation of a brake controlling valve device,not shown, when an application of the brakes is being eifected. H

The cut-oil valve device 32 is interposed between the supply pipe 33and'the brake cylinder device 30 and comprises a casing having formedtherein a valve chamber 35 containing a valve 36 that is normally heldin unseated position by the force of a coil spring 31 and is arrangedfor movement to seated position upon energization of a magnet 33. Thevalve chamber 35 communilikely to result in sliding of the wheel, theconsequent sudden reduction in the rotative speed of the shaft 5 and ofthe hub member I carried thereby is effective to cause the heavy annularmember I0 01 the fly-wheei device 6 to overtravel the hub member due toits. inertia, while the flexible web element 3 is correspondinglydistorted.

As the annular member In is thus yieldingly deflected with respect tothe hub member I of .the fly-wheel device, the contact element 2| iscarried into engagement with one or the other or the connected contactelements 20, depending .upon the direction of rotation of the fly-wheeldevice, thereby establishing a circuit which includes the positiveterminal of a battery 50, a. grounded conductor 5|, a grounded conductor52, the coils of the magnets 33 and 45, a c0nductor 53, a brush 54engaging the slip ring 28, the conductor 21, the connected contactelements 20 and2l, the conductor 22, the slip ring 24, a brush 56 incontact therewith, and a return conductor leading to the negativeterminal of the battery.

Upon energization of the magnet 38 the valve 36 is shifted to its seatedposition against the force of the spring 31, thereby cutting off furtherflow of fluid under pressure from the pipe 33 to the brake cylinderdevice 30. At the same time, as the magnet 45 becomes energized, thevalve 42 is forced downwardly and away from its seat to eifect ventingof fluid under pressure from the brake cylinder device 30 by way of thepipe 39 and the port 44. The braking force exerted by the brake cylinder30 is thus rapidly reduced and the slipping wheel or wheels accordinglycease to decelerate and begins to accelerate rapidly .back toward aspeed corresponding to vehicle gment 2| to be shifted from engagementwith one cates at all times through a pipe 38 with the brake cylinderdevice 30, and with the valve 33 unseated also communicates with thesupply pipe 33. I

The ventvalve device 3| comprises a casing having a valve chamber 4|communicating with the pipe 39 and containing a valve 42, which isnormally held in seated position bythe force of a coil spring 43, and ismovable to an unseated of the contact elements 20 into contact with theopposite contact element 20. The circuit for energizing the magnetwindings 3B and 45 is thus momentarily interrupted during thetransitionary period from deceleration to acceleration of the slippingwheel. The magnet windings 38 and II are however connected in Paralleland are therefore short circuited, as shown, and due to the inherentinductance thereoi' remain energized sufliciently long to prevent achange of poposition for connecting the chamber 4| to an 15 sition ofthe valves 36 and 42 during the transition from deceleration toacceleration of the slip- In any event,

ping wheels. Even though the valves 36 and 42 should be momentarilyrestoredto the normal position thereof as shown in the drawing upon themomentary interruption of the circuit for energizing the magnet windings38 and 45, fluid under pressure would be supplied only momentarily fromthe supply pipe 33 to the pipe-39 and connected brake cylinder 30, afterwhich such fluid under pressure would again be exhausted upon completionof the circuit in response to the acceleration of the slipping wheels.

When the slipping wheels having a driving connection with the shaftcease to accelerate at a sufflciently rapid rate, the inherentresiliency of the web element 9 restores the annular inertia member IIIto its normal position with respect to the hub member I. Contact element2| is thus once more centered between and out of contact with thecontact elements 20, thereby interrupting the circuit of the magnetwindings 38 and 45. Valves 36 and 42 are thus restored to their unseatedand seated positions respectively, in which the exhaust of fluid underpressure from the brake cylinder 30 is terml-,

nated and fluid under pressure is resupplied to the brake cylinder toeffect reapplication of the brakes.

If, upon reapplication of the brakes, the wheels again begin to slip,the above cycle of operation is repeated.

In Fig. 3 of the drawing, the fly-wheel device 6 is illustrated inslightly modified form, it being understood that the device, althoughshown in a fragmentary view, is adapted to form part of a brake controlsystem such as that shown in Fig. 2. The elements of the fly-wheeldevice 6 shown in Fig. 3 are the same as those of the fly-wheel deviceshown in Fig. l, and include the shaft 5, the hub member "I, theflexible web element 9, and the annular inertia member 6, but

it will be observed that the spaced apertures l5 formed in the webelement are fitted with plug elements 60 in place of the cylindricalelements l1 shown in Fig. 1. Each of the plug elements 60 is generallycircular in form for insuring a close fit with the correspondingaperture I5, and is provided with oppositely disposed flat surfaces orrecesses 5| defining relatively narrow open spaces in the web element 9.It will be apparent that when the web element 9 is distortd due toovertravel of the annular inertia member ill with respect to the hubmember 1, the open spaces adjacent the surfaces 8| of the plug elementsare adapted to receive the flexible material of the web element that istemporarily distorted out of the normal position, so that the fiy-wheel'device 6 is thus rendered freely defiectable in a rotary direction. Atthe same time the plug elements 60 are effective to prevent undesiredcollapse or undue distortion of the web element 9, such as might permitdisplacement of the annular inertia member l0 out of concentricalignment with the hub member I.

While I have shown my rotary inertia operated control device inconnection with a brake control equipment, it will be apparent that itmay be employed in connection with a propulsion control apparatus ormerely for signal purposes. the particular construction which I'haveprovided avoids heretofore encountered difiiculties incidental tohearing mounted flywheels in rotary inertia devices as well as complexspring driving mechanism associating the fly-wheel and its drivingshaft.

I 3 Having now described my invention, what I claim as new and desire tosecure by Letters Patent, is:

1. An inertia operated device comprising, in combination, a rotatablemember subject to rapid changes in the rotational speed thereof, a bodyhaving a pronounced inertia characteristic, a resilient deformable meanssupporting said body on said member and arranged to rotate said body andmember together and effective to permit said body to move rotativelyrelative to said member upon sudden changes in speed of rotation of saidmember, and a control mechanism governed by the relative. rotativemovement between said body and member.

2. A rotary inertia operated control device for detecting the rate ofchange of speed of a rotary element, said device comprising a'memberrotatable according to the speed of the rotary element, an annularinertia element, an annular member of resilient deformable materialinterposed between said rotatable member and annu lar element forsupporting said annular element in concentric relation to the rotatablemember and yieldingly deformable to permit limited rotative movement ofthe annular element with respect to said rotary member, and meansoperated in response to the rotative movement of the annular elementwith respect to the rotary member.

3. A rotary inertia operated control device for detecting the rate ofchange of speed of a rotary element, said device comprising a memberrotatable according 'to the rotation of said rotary element, an annularinertia element, an annular member of resilient deformable materialinterposed between said rotatable member and said inertia element andsecured respectively thereto effective to normally support said'ann'ular element in concentric relation and in a given rotary positionwith respect to said rotatable member as long as said rotary elementrotates at .a constant speed and effective to permit limited rotativemovement of the annular element in opposite directions with respect tothe rotatable member in response to changes in the speed of the rotaryelement, and switch means operated in response to predetermined rotativemovement of the annular element in either direction out of its normalrotative position with respect to the rotatable member.

4. A rotary inertia operated control device for detecting the rate ofchange of speed of a rotary element, said device comprising a hubelement driven according to the rotation of the rotary element, anannular inertia member, an annular web member of rubber-like materialsecured to the hub element and to said annular member and normallysupporting said annular member in concentric relation'and in a certainnormal rotative position with respect to the,

said hub member, said web member being torsionally yieldable to permitlimited rotary movement of said annular member relative to said hubelement in accordance with the rate of tary element, said devicecomprising a hub ele- .ment driven according to the rotation of therotary element, an annular inertia member, an annular web member ofresilient rubber-like material having a thick central portion secured tovsaid hub element and tapering radially in cross section to a relativelythin peripheral portion which is secured to said annular inertia member,said web member being eflective to support said annular inertia membernormally in concentric relation and in a certain normal rotativeposition with respect to said hub element and being torsionallyyieldable to permit limited rotative movement or said annular inertiamember in either direction out of its certain normal rotative positionwith respect to said hub element in response to changes in the speed ofrotation of said rotary element, and means operated in response to apredetermined displacement of the annular inertia member out of itsnormal rotative position with respect to said hub element.

6. A rotary inertia operated control device for detecting the rate ofchange of speed of a rotary element, said device comprising a hubelement driven according to the rotation of the rotary element, anannular inertia member, an annular web member of resilient rubber-likematerial secured to said hub element and said annular inertia member ininterposed relation therebetween for supporting said annular inertiamember in concentric relation to the hub element and in a certain normalrotative position with respect thereto, said web member beingtorsionally yieldable to permit rotative movement of said annularinertia member relative to said hub element in' response to changes inthe rotational speed of the rotary element, reinforcing means associatedwith said web member for assisting said web member in maintaining theconcentricity of the annular inertia member with respect to the said hubelement and at the same time being effective to limit the rotarydisplacement oi the annular inertia member with respect to thehubelement, and means operated in response to the rotative movement ofthe annular inertia member with respect to the hub element.

7. A rotary inertia operated control device for detecting the rate ofchange of speed of a rotary element, said device comprising a hubelement driven according to the rotation ofthe rotary element, anannular inertia member, an annular web member of resilient materialsecured in interposed relation to said hub element and said 8. A rotaryinertia operated controldevice for detecting the rate of change of speedof a rotary element, said device comprising a hub element drivenaccording to the rotational speed of a rotary element, an annularinertia member, an annular web member of resilient material interposedbetween and secured to said hub element and inertia member forsupporting said annular inertia member in concentric relation to the hubelement and in a certain rotative position with respect thereto andbeing torsionally yieldable to permit the rotative movement oi theinertia member with respect to the hub element in response to changes inthe rotational speed of the rotary element, said web having a pluralityof circular apertures therein, a plurality of substantially cylindricalplug elements fitted into said apertures whereby to assist said webmember in maintaining concentricity of the inertia member with respectto the hub element and effective also to limit the rotative movement ofthe inertia member with respect to the hub element, and

hub element.

means operated in response to the rotative movement of the inertiamember with respect to the 9. A control device comprising a rotarymember arranged to be driven at different speeds, a continuous annularmember having a pronounced inertia characteristic, resilient annularmeans interposed between and fixed to said annular member and saidrotary member, said resilient annular means being so constructed as tosupport said annular member in substantially concentric relation to andin a certain rotative position relative to said rotary member and topermit said annular member to torsionally ,deform it a substantialamount in response to a change in the rotational speed of the rotarymember at a rate exceeding a certain rate to thereby cause relative 40rotational movement .of the annular member out annular inertia memberfor supporting said annular inertia member in concentric relation and ina certain normal rotative position with respect to the said hub element,said web member being torsionally yieldable to permit rotative movementof the annular inertia member with respect to the said hub element inresponse to the changes in the rotational speed of the rotary element,said v'veb member having. a plurality of apertures, cylindricalrelatively rigid elements fitted into said apertures for assisting saidweb member in maintaining the concentricity of the annular inertiamember with respect to the hub element and etiective at the same time tolimit the degree of rotative movement of said inertia member withrespect to said hub element, and means operatively responsive to therotative movement of the inertia member with respect to the hub element.

of its said certain rotative position with respect to said rotarymember, and switch means operatively responsive to relative rotationalmovement of said inertia member with respect to said. rotary member.

10. A circuit controlling device comprising a rotary member operable atvarying speeds, an

annular element of resilient fiexible material having a central hubportion and an outer portion extending radially outward from the hubportion, the hub portion of said annular element being secured to saidrotary member with the outer portion in concentric relation to androtatable in a plane perpendicular to, the axis of rotation of saidrotary member, an annular member fixed on the periphery of the outerportion of said element and having a pronounced inertia characteristicvso as to cause torsional deforma-' ti-on of the outer portion of saidelement to thereby permit said annular member to shift rotatively asubstantial amount with respect to the rotary member upon a suddenchange in speed of the rotary member, and switch means operative uponrotational movement of the said annular member with respect to saidrotary-member.

GEORGE K. NEWELL. I

